Many business establishments use a private branch exchange (PBX) system to make connections among their internal telephone lines and connect the internal lines to a public switched telephone network (PSTN). A PBX system often includes extensions to other devices such as fax machines, modems, etc. Further, many PBX systems include extensions to mobile devices (e.g., cellular phones, smart phones, etc.). The PBX extension to mobile allows the users to use their mobile devices as virtual extensions of the PBX and benefit from features of PBX, such as single number reachability (SNR) and simultaneous ringing. For example, using the single number reachability feature of PBX, an office worker using the PBX extension to mobile may use his/her personal cell phone to receive business calls incoming to his/her office phone. Similarly, using the simultaneous ringing feature of PBX, the office worker's business phone and cell phone ring simultaneously so that he/she can receive calls incoming to his/her office phone at his/her cell phone.
Due to the increasing number of individuals that spend time away from their work environments, either by telecommuting, working from client locations, or working while traveling, many business establishments have been moving away from their traditional settings and investing in providing their employees with mobile and remote communications capabilities. Although, features such as the PBX extension to mobile may be used, existing features are costly to set up and do not provide the user with the ability to access their personal number and their business number using their smart phone.